| 摘要 |
PURPOSE:To obtain a combination ring excellent with wear resistance and heat resistant settling, by selectively applying a mother material of both steel side rail and spacer expander, when soft nitriding treatment is applied to the side rail and the spacer expander to form the combination oil ring. CONSTITUTION:A combination oil ring consists of side rails 1 and a spacer expander 3, axially and radially supporting the side rail, and a peripheral surface 11 of the side rail is slidably contacted to a cylinder internal peripheral surface 51, further an internal peripheral surface 13 of the side rail is slidably contacted to a protrusion 31 of the spacer expander. Mother material basic composition of the side rail is dispersed with 3-7% fine granular carbide by area ratio of tempered martensite not more than 10mu with hardness of HV1,200-1,500, and a nitriding compound of total hardness HV1,300-1,500 is provided at least 2mu on the surface, while mother material basic composition of the spacer expander is of austenite and provided with a nitriding compound layer of HV800-1,000 at least 2mu on the surface. |
